JPH03266745A - Fiber moulded body of flexible bag and manufacture thereof - Google Patents

Abstract

PURPOSE:To eliminate need of sewing and improve the productivity for a tape of fiber filaments disposed linearly and wound like a bag by fusing fiber elastomer and using obtained material for the matrix of the tape. CONSTITUTION:For manufacturing an air bag of a fiber moulded body of a flexible bag for protecting passengers in a vehicle at the time of colliding,a tape of opened fiber yarn 1 obtained by mixing filament yarn of polyparaphenylene-3,4 diphenyl ether-terephthalic amid and filament yarn of urethane-based theremoplastic elastomer, drawing a plurality of obtained coming yarns into a two, and opening it is sent through rollers 2 - 7 to be wound around a disc-shaped mandrel 10 uniformly without having gaps through a delivery eye 8 capable of reciprocation. The whole body of the mandrel is then heated and pressurized to fuse the urethane elastomer, so monofilaments of the fibers are bonded to each other strongly by the elastomer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flexible bag fiber molded product and a method for manufacturing the same.

[Conventional technology]

As a flexible bag fiber molded product, one that is used in an airbag that expands during a vehicle collision, absorbs the shock of a seated occupant, and protects the occupant is known.

Airbags are designed to explode gunpowder and instantaneously pump gas into the bag, so they must be able to withstand the impact.

The conventionally provided airbags are:
After forming a polymer coating on one side of a flat woven fabric, the two coated woven fabrics are stacked so that the coated sides face each other, and the periphery is sewn to form a bag.

For example, in the prior art section of Japanese Patent Application Laid-open No. 51-4742 (invention related to a bag for an airbag device and a manufacturing method thereof), it is stated that ``a circular piece of cloth is cut out from two square pieces of cloth and the periphery is sewn together. "Manufacturing a flat airbag" is disclosed.

[Problem to be solved by the invention]

However, the method of manufacturing airbags by sewing involves many manual steps and is difficult to automate, making it impossible to manufacture economically. There are problems such as the time and effort required to test the air permeability, and in addition, there is the problem that there is basically no sufficient confidence in the sewing itself.

Therefore, if an excessively strong and thick woven fabric is used to improve reliability, the airbag becomes bulky and cannot be stored compactly in the center of the steering wheel or the like.

The present invention has been made in view of the problems of the prior art, and its purpose is to provide a flexible bag that is homogeneous, highly reliable, easy to manufacture, can be stored compactly, and is lightweight. An object of the present invention is to provide a fiber molded product and a method for producing the same.

[Means to solve the problem]

In order to achieve the above object, the gist of the present invention is to provide a flexible bag fiber molded article in which a tape in which fiber filaments are arranged in a substantially linear and parallel state is wound into a bag shape. The first invention is a flexible bag fiber molded article characterized in that the matrix of the tape is obtained by melting an elastomer, and the present invention includes filament yarns of fibers and filament yarns of fibrous elastomer for forming the matrix. The filaments of this commingle yarn are arranged in a substantially linear and parallel state to obtain a tape-like product. A second invention provides a method for manufacturing a flexible bag fiber molded article, which is characterized in that it is manufactured by winding it around a mandrel having a shape, and includes a filament system of fibers and a filament yarn of a fibrous elastomer for forming a matrix. The filaments of this commingle yarn are arranged in a substantially linear and parallel state to obtain a tape-like product, and this tape-like product is heated to form a matrix. A flexible bag characterized in that it is manufactured by melting only a forming filament to form a tape matrix, and winding the resulting tape around a mandrel having a predetermined size and shape. The third invention is a method for producing a fiber molded product, in which a commingle yarn is obtained by mixing filament yarns of fibers and filament yarns of a fibrous elastomer for forming a matrix, and then the filaments of this commingle yarn are made into a substantially straight shape. A tape-like material is obtained, which is arranged so as to maintain a parallel state, and after wrapping this tape-like material around a mandrel having a predetermined size and shape, matwax is produced by heating the entire mandrel. A fourth invention is a method for manufacturing a flexible bag fiber molded article, characterized in that the tape matrix is formed by melting only the forming filaments.

In the specification of this application, "tape-like thing", "tape j
, "Matrix" and "Commingle Yarn" refer to the following:

(a) Tape-like material: one or several yarns (multifilament threads) arranged in a sheet-like manner so that the monofilaments remain substantially straight and parallel.

(b) Tape - A product in which the monofilaments constituting the above-mentioned tape-like material are mutually bonded and integrated.

(C) Matrix - The portion of the above tape excluding the fiber filaments.

(c) Commingle yarn = Yarn that is a mixture of fiber filament yarn and fibrous elastomer filament yarn for matrix formation.

The fibers of the present invention typically include human silk, polyvinyl alcohol fibers, aliphatic and aromatic polyamide fibers,
Examples include polyester fibers, carbon fibers, glass fibers, etc., but are not particularly limited.

The fibrous elastomer for forming the matrix of the present invention is preferably one that has flexibility and appropriate elasticity when the matrix is formed. Examples of the fibrous elastomer include polyester, polyamide, urethane, olefin, etc. Thermoplastic elastomers are preferred.

The melting points of the fibers constituting the commingle yarn of the present invention and the fibrous elastomer for matrix formation are not particularly limited as long as the melting point of the fibers is 30°C or higher, preferably 60°C or higher. do not have.

The fineness of the commingling yarn of the present invention is not particularly limited, but is generally in the range of 30 to 30,000 D. Of course, these do not necessarily need to be supplied with a single thread; rather, it is easier to spread horizontally if a plurality of threads are supplied at the same time.

The thinner the seven filament fineness is, the easier it is to spread, and a range of, for example, 0.8 to 10D is generally preferred.

In addition, the volume content of fiber in commingle yarn is 50
-95%, preferably 60-90%.

If the value is larger or smaller than this value, the object of the present invention cannot be fully achieved.

Methods for opening the commingle yarn of the present invention include electrical methods, mechanical methods, methods using air flow, etc., but any method may be used as long as the purpose can be achieved. Any method such as that disclosed in Japanese Patent No. 69626 may be used.

Note that the tape-like material obtained by the opening must be extremely uniform (with little variation in thickness). In addition, the monofilaments must be completely separated from each other, and their spacing must be close enough that the average spacing is less than the average filament diameter.

In the present invention, methods for wrapping tape or a tape-like material around a mandrel having a predetermined size and shape can be mechanically divided into traverse method, rotating arm method, and other methods in which the arm or mandrel has a special rotational movement. Any special type of winding can be applied.

Divided by shape, there are three methods: a method for wrapping closed shapes such as a cocoon, a sphere, and a cone, a method for wrapping a shape such as a cylinder or a disk, and a method for wrapping an irregular shape such as a prism or pyramid. But it can be applied.

Although there are various winding patterns, a predetermined strength can be imparted by broadly classifying them into parallel winding, helical winding, longitudinal winding, or a combination thereof. In cases where pressure is generated inside the bag, such as in an airbag, by forming the bag with a laminated structure of at least two or more layers with different winding directions, the pressure can be applied uniformly.

When molding into a removable shape, use a deformable hollow mandrel, such as a metal mandrel (which can be disassembled if necessary) or a rubber mandrel, and mold it into a closed shape. If so, use a consumable mandrel made of gypsum, rock salt, easily fused metal, etc. In order to easily remove the mandrel after molding, it is desirable to apply a mold release agent to the mandrel in advance.

The fibrous elastomer for matrix formation may be melted before or after the tape is wound around a mandrel having a predetermined size and shape. The method involves heating the commingle yarn above the melting point of the fibrous elastomer to form a tape matrix before winding the tape around a mandrel, and then applying the resulting tape to a predetermined method. method of winding it around a mandrel and cooling it afterwards" or "
It is possible to adopt one of the following methods: wrapping a tape-like material around a mandrel in a predetermined manner, heating the entire mandrel, melting only the fibrous elastomer to form a tape matrix, and then cooling it. can.

The heat and pressure treatment applied to tape-shaped products uses a fibrous elastomer to fuse the filaments of adjacent fibers in a crossed or parallel state, and maintains the troublesome state after demolding, while also maintaining the filaments of the fibers. This is done for the purpose of protection. The temperature condition is preferably a temperature at which the fibrous elastomer exhibits a predetermined adhesive force, that is, 120 to 190°C. Considering thermal decomposition of the elastomer, the heating temperature is 200°C
Harsh conditions such as heating time of 20 minutes or more at temperatures above 10°C should be avoided.

[Effect]

Since the bag is obtained by winding a tape-shaped filament around a mandrel, there is no need for sewing, and since the fiber filaments are bonded with an elastomer, the resulting bag is flexible and can be folded freely. It is strong because it is reinforced with fiber filaments.

As described above, according to the present invention, a strong flexible bag fiber molded product having an integral structure can be obtained easily and inexpensively.

〔Example〕

Examples 1 and 2 of the present invention will be described below.

(Example 1) In Fig. 1, 1 is a filament yarn of 1500 D of polybara phenylene/3.4 diphenyl ether/terephthalamide and 1 of a urethane thermoplastic nylastomer.
500. This tape is a tape-shaped spread yarn obtained by opening five commingle yarns mixed with filament yarns using the commonly used electric method to form a tow. The spread yarn 1 is passed through rollers 2.3, between opposing rollers 4.50, and then through rollers 6.7, and then reciprocated in a direction parallel to the rotation axis 9 of the disc-shaped mandrel lO. A decomposable metal disc-shaped mandrel 10 coated with a mold release agent in advance through an eye 8
The tape-shaped spread yarn 1 was wound uniformly around the top at a winding angle of 14.5° and a feed rate of 0.45 m/see until there were no gaps.

After this, the whole mandrel was heated at 180℃ and 0.5kg/cm.
The urethane elastomer was melted by heating and pressurizing under the following conditions, and the urethane elastomer was firmly bonded between the monofilaments of the fibers. As shown, it is extremely thin with a thickness of 40 μm and a width of 8 mm.In FIG. 2, 12 is a monofilament of fibers, and 13 is a matrix made of urethane elastomer.

Next, the disc-shaped mandrel 10 was disassembled and the bag formed on the mandrel was taken out.

(Example 2) As a mandrel, a disk-shaped mandrel 1 shown in FIG.
0 instead of a butyl rubber diameter 5 as shown in Figure 3.
The structure is the same as that of Example 1 except that the hollow spherical mandrel 14 manufactured by 00Kaku was used.

In FIG. 3, 15 is a valve for injecting air, 16 is an air supply vibrator, and 17 is a small hole bored in the air supply vibrator. The end plate 18 installed on the air supply vibrator 16 had a diameter of 50 mm.

In the state shown in the figure, the valve 15 is opened and air is blown into the spherical mandrel 14 through the small hole 17 of the air supply vibrator 16.
A state in which the internal pressure of the spherical mandrel 14 is 0.3 kg/c+m'' is shown.

After applying a mold release agent for rubber molds to the spherical mandrel 14 using a spray gun, the tape-shaped spread yarn 1 is wound onto the spherical mandrel 14 through the delivery eye 8 at an angle of 14. , 5° tape-shaped spread yarn was wound uniformly at a feed rate of 0.45 m/sec until there were no gaps. After that, further air is injected into the spherical mandrel 14 through the valve 15 to bring the internal pressure of the spherical mandrel 14 to zero.
．． 5 kg/Cm”, and this mandrel was
The urethane elastomer was melted by leaving it in an oven (not shown) at 80''C for 10 minutes, and the monofilaments of the fibers were firmly bonded with the urethane elastomer.

After this, remove the mandrel from the oven and let it stand at room temperature for 30 minutes.
After cooling for several minutes, open the valve 15 to remove the air inside the mandrel, and insert the butyl rubber mandrel into the air supply vibrator 1.
6, and a spherical bag 19 as shown in FIG. 4 was obtained. The weight of this bag was 270 g.

(Comparative Example) As a comparative example, a plain woven fabric having a warp density and a weft density of 24 threads/::' was produced using 840 denier yarn. Next, a rubber solution prepared by dissolving a rubber composition containing chloroprene rubber as a main component in toluene was applied to one side of this plain woven fabric. This application amount is 65 g/l in terms of solid content.
A''. Then, two pieces of woven fabric were obtained by vulcanizing at 150°C for 14 minutes and coated with a rubber solution on one side, and a spherical bag was made from these two woven fabrics by sewing. The weight of the bag was 360 g.

(Performance comparison test) Next, the pressure resistance, storability, and expandability of the spherical bag according to Example 2 and the spherical bag according to the comparative example were as follows.
A comparative test was conducted according to the following method.

■Pressure resistance 1000 for each example and comparative example
Each bag was prepared, and an internal pressure of 2 kg/cm'' was applied to each bag, and the number of bags that did not burst was counted.

■Storability The height when the bags were folded to a 20 CI angle and stacked was measured and expressed as an index with the height of the comparative example as 100. The lower this index is, the more flexible and excellent the storage property is.

■ Deployability When an internal pressure of 2 kg/cra'' was applied to the bag, the time required for the tip of the bag to completely reach the expanded position was measured and expressed as an index with the comparative example being 100. The lower the index, the better the speed and developability.

The above test results are shown in Table 1 below.

Table 1 As is clear from Table 1, the bag according to this example weighs 2 kg.
/cm'' pressure test, none of the 1,000 pieces burst, but 9 pieces in the comparative example burst.
The rupture location was the sewing area.

Furthermore, the bag according to this example is significantly superior to the comparative example in terms of storability and expandability.

〔Effect of the invention〕

■The flexible bag fiber molded product according to the present invention is different from bags made from woven or knitted fabrics, and has a structure in which an extremely thin tape or tape-like material is wound around a mandrel. It is easy to make, compact, and reliable, and does not require sewing, making it possible to streamline the production process.
A tough flexible bag fiber molded article having an integral structure can be manufactured at low cost.

(2) In the present invention, since an elastomer is used to bond the fiber filaments, the resulting flexible bag fiber molded product is flexible and can be folded freely.

(2) In the present invention, the fiber filaments are fused to each other by an elastomer and remain in that state to maintain the strength of the molded product. As described above, according to the present invention, a strong flexible bag fiber molded product reinforced with fiber filaments can be obtained very easily. Furthermore, by changing the shape of the mandrel, bags of complex shapes can be obtained as desired.

■Since the present invention allows a strong bag of any shape to be integrally molded, the flexible bag fiber molded product according to the present invention
In particular, it has an exhaust port, a mounting port, etc., and is ideal for automotive airbags that require high strength. In addition, by changing the ratio of filament and elastomer using the technology related to the present invention, it can be used for gases such as hot air balloons, atto balloons, balloons such as airships, shock absorbing bags when high-speed moving objects collide, It can be used in gas bags to block explosion blasts, flexible containers for powder, fuel tanks and water storage tanks for liquids, and heat-resistant insulation materials for civil engineering construction work.

[Brief explanation of drawings]

Fig. 1 is a side view of each process showing an embodiment of the present invention, Fig. 2 is a cross section of one tape and an enlarged view of the mandrel edge, Fig. 3 is a sectional view of a spherical mandrel and an air supply vibrator, and Fig. 4 is a cross-sectional view of a spherical mandrel and an air supply vibrator.
The figure is a plan view of the bag. 1...Tape-shaped spread yarn, 10...Disc-shaped mandrel,
11...Tape, 12...Fiber monofilament,
13... Matrix, 14... Spherical mandrel, 19
・Bag body? - to Figure 1 Figure 3 Figure 4 Figure 2

Claims (1)

[Claims] 1) In a flexible bag fiber molded product obtained by winding up a tape in which fiber filaments are arranged in a substantially linear and parallel state into a bag shape, a fibrous elastomer is melted. A flexible bag fiber molded product characterized in that the obtained product is used as the matrix of the tape 2) A commingle yarn is obtained by mixing filament yarns of fibers and filament yarns of fibrous elastomer for matrix formation. Next, a tape-like product is obtained in which filaments of this commingle yarn are arranged in a substantially straight and parallel state, and this tape-like product is wound around a mandrel having a predetermined size and shape. 3) A method for producing a flexible bag fiber molded article, characterized in that a fiber filament yarn and a fibrous elastomer filament yarn for matrix formation are mixed to obtain a commingle yarn, and then the commingle A tape-like product is obtained in which yarn filaments are arranged in a substantially linear and parallel state, and by heating this tape-like product, only the matrix-forming filaments are melted to form the matrix of the tape. A method for manufacturing a flexible bag fiber molded product, characterized in that the resulting tape is wound around a mandrel having a predetermined size and shape 4) Formation of a matrix with filament yarns of fibers A commingle yarn is obtained by mixing filament yarns of a fibrous elastomer for use in the manufacturing process, and then a tape-like product is obtained in which the filaments of this commingle yarn are arranged in a substantially straight and parallel state. The tape is wound around a mandrel having a predetermined size and shape, and then the entire mandrel is heated to melt only the matrix-forming filaments to form the matrix of the tape. Method for manufacturing flexible bag fiber molded product